Mainspring-retainer and automatic safety-release.



0. A. HUBERTY.

MAINSPRING RETAINER AND AUTOMATIC SAFETY RELEASE.

APPLICATION FILED MAY 10. 191-6.

1 1 98,382 Patented Sept. 12, 1916.

Oliver)? fifwizemry OLIVER A. HUBERTY, LONDON, ENGLAND, ASSIG-NOR TO THE AUTOMATIC ARMS COMPANY, OF BUFFALO, NEW YORK, A CORPORATION OF NEVI' YORK.

MAINSIPRING-RETAINER AND AUTOMATIC SAFETY-RELEASE.

Specification of Letters Patent.

Patented Sept. 12, 11916.

Application filed May 10, 1916. Serial No. 96,515.

To all whom it may concern:

Be it known that I, OLIVER A. HUBERTY, a citizen of the United States, residing at 27 Pall Mall, London, England, have invented certain new and useful Improvements in Mainspring-Retainers and Automatic Safety-Releases, of which the following is a specification.

This invention has special reference to mainsprings designed for ready removal and replacement such as are used in the automatic gas-operated firearms of the Lewis type. Therein the mainspring is in convolute form housed in a removable casing to the rear of the gun barrel and pro-v vided with means for holding the spring under tension at the time it is applied to the receiver, which holding means is automatically released in the act of fastening the casing with its contents to the receiver, at which time also the spring is connected to the mechanism it is to drive. It is essential that such incased springs may be readily withdrawn and inserted in such casing. A center pin easily removable from the exterior of the casing is therefore employed for this purpose and holds the inner end of the spring tothe casing. Provision is also made for the automatic release of the hold of the pin upon the spring in case the latter. should be allowed to suddenly run down. This is of importance since it is the overrunning of a convolute spring whose outer end is suddenly released that causes its inner end to break or become detached from its pin or arbor. Such accidental release most' frequently takes place when the spring is dissociated from the mechanism operated thereby. The present invention is obviously applicable wherever removable convolute springs are similarly employed.

To these ends therefore this invention consists in the structure of parts for the purpose specified and in the combination,

thereof substantially as hereinafter set forth and claimed.

In the accompanying drawings which form a part of this specification Figure 1 is a vertical longitudinal section through the mainspring mechanism, the plane of section being indicated on Fig. 3 by line 1-l, and also shows the parts of the gun immediately associated with said mechanism.

gear on the drum by 13, the removable housing or spring casing by 14, the springpressed detent for holding the mainspring under tension by 15 and the removable attaching and automatically detachable center pin for the inner end of the mainspring by 16. The rack 17 on the gasdriven piston rod 18 (shown in dotted lines) is that with which the gear 13 engages for returning said rod by the power stored in the spring 10 under the action of the gas.

The casing 14 is applied to the receiver '9 by inserting the hook 19 over the pin 20 then the rear end of the casing is swung up and caught and held by advancing the forward end of the grip slide 21 under it. In this act the detent 15 is released by said forward end wedging under the tail thereof and the power of spring 10 is then exerted upon said rack.

The detachability of the spring casing and application of the convolute spring above referred to are more fully set forth in they patent to Isaac N. Lewis, No. 1,142,896, June 15, 1915, and are here presented merely to give the proper setting for the present invention, the chief features of which reside in the pin 16 and immediately associated features and parts. Said pin is provided with a screw thread, Figs. 5 and 6, and with a head 22 which when the pin is seated will hold it normally in place. About this pin and threaded to it is the collet 23 to which the inner end of the spring 10 is attached. The pin 16 has bear ings at its ends in the sides of casing 14. To engage the head of said pin and hold it against turning when seated projections are formed upon one side of the casing 14 at opposite sides of the pin hole. These projections really constitute a boss 2% having a lot through the middle thereof in which slot the head of the pin rests when in place. The collet 23 has bearings at its ends in the heads of the drum 11 but does not protrude beyond the heads. Upon the removal of the pin 16 the drum and its contents are therefore readily removable from the casing 14:. To insert a drum it is slid into the casing in position such'that it will wind the spring when the protruding gear is .rotated toward the detent 15. Then the pin is screwed in till its head reaches the boss 24 and is in line with the slot therein. Then by rotating the protruding gear toward the detent said head is drawn fully into the slot and the pin held against turning so long as the spring is under tension. Before the casing and its spring are applied to the receiver more tension is given to the spring, in the manner above described, up to the desired degree for operating the parts it is to drive. The spring detent 15 holds this tension till released as above described on application of the casing to the receiver.

T 0 remove the mainspring the casing is taken down from the receiver. In this act the detent 15 again becomes automatically effective in holding the drum from rotation. Then by withdrawing the detent from the drum gear by pressing up on its tail the drum will be allowed to run freely and will permit the spring to carry the collet around with it thereby forcing the pin 16 longitudinally till the head thereof is out of the slot in boss 24, see Fig. 6, when the pin and collet Will rotate freely with the spring. No matter how sudden the release of the drum may be the overrunning of the spring will simply carry the collet around with it and throw the pin out without danger 'of breaking the spring from the collet. The pin may then be replaced and the spring or a new one put under tension again as above described.

The invention claimed is 1. In an automatic gas-operated gun the combination with the gas piston rod having a rack gear thereon, of a spring drum having a spur gear, a casing for said drum removably attachable to the gun for the interaction of said spur and rack gears, a convolute spring in said drum having its outer end attached thereto, means for holding said j spring under tension when said casing is detached from the gun, and an automatically removable retaining pin connecting the inner end of said spring to said casing.

2. In an automatic gas-operated gun the combination with the gas piston rod having a rack gear thereon, of a spring drum having a spur gear, a casing for said drum re- 'mo vably attachable to the gun forthe interaction of said spur and rack gears, a convolute spring in said drum having its outer end attached thereto, a collet attached to the inner end of said spring and journaled in said casing, a detent for holding said spring under tension when 'said casing is detached from the gun, and an automatically removable pin for retaining said collet in said casing and preventing rotation thereof by the spring when under tension.

3. In an automatic gas-operated gun the combination with the gas piston rod having a rack gear thereon, of a spring drum having a spur gear, a casing for said drum removably attachable to the gun for the interaction of said spur and rack gears, a convolute spring in said drum having its outer end attached thereto, a collet attached to the inner end of said spring and free to rotate in said casing, a readily removable pin screwthreaded through said collet and having bearings at its ends in said casing, and means for preventing the rotation of said pin while said spring is under tension.

4. In an automatic gas-operated gun the combination with the gas piston rod having a rack gear thereon, of a spring drum-haw ing a spur gear, a casing for said drum removably attachable to the gun for the interaction of said spur and rack gears, a convolute spring in said drum having its outer end attached thereto, a collet attached to the inner end of said spring and free to rotate in said casing, a detent for holding said drum against rotation, a readily removable polyg- (")rial headed pin screwthreaded through "said collet and having bearings at its ends in said casing, a boss on said casing having a slot in which said head may be seated while the spring is under tension and from which said head may be released by longitudinal movement of the pin when the drum is released from the detent and the spring is allowed to unwind and overrun.

The combination with a convolute spring working on a fixed inner end, of an automatically removable retaining pin for said end, motor mechanism attached to the outer end of said spring, and means for holding the spring under tension at will.

(5. The combination with a convolute spring working on a fixed inner end, of a casing therefor, mechanism at the outer end of said spring to be driven thereby,'means for holding the spring under tension at will, and an automatically removable pin for nor- .mally confining said spring by its inner end in said casing.

7. The combination with a convolute spring working on a. fixed inner end, a casing therefor, a gear member attached to the outer end of said spring, meansn for holding said spring under tension, a collet free to rotate in said casing and having the inner end of the spring connected thereto, and an automatically removable pin passing through said collet for normally holding it against rotation.

8. The combination of a. convolute spring working on a fixed inner end. of a when the spring is permitted to overrun on 15 easing therefor, a eol'let tree to rotate in said easing and having the inner end of the spring eonneeted thereto. a pin sere\\'thre:ul ed through said eollet and having hearings at its ends in the sides of said casing. and means for holding said pin against rotation while being moved a definite distanee longitndinally hy the rotation of said eollet.

U. The combination with a eonvolnte spring working on a fixed inner end and havinq its outer end adapted for removahle application to mechanism to be driven therehv. and means for freeim its inner endv unwinding.

It). The eomhination of a eonvolnte spring. means for delaehahly connecting its outer end to meehanism to he driven thereby a eollet attached to the inner end of the spring. means for holding the collet against rotation while the spring is under tension, and means for releasing the eollet when the outer end of the spring is released and the spring allowed to overrun.

In testinrol1 whereof I have atlixed my signature.

OLIVER A. HUBER"): 

